Flotation reagent



Patented June 6 1933 UNITED STATES PATENT OFFICE FREDERICK G. MOSES, 01' NEW YORK, N. Y., AND EDWARD J. CARAVAN, OF 'WDODGLIIEF, NEW JERSEY, ASSIGNORS TO THE BARRETT COMPANY, A. CORPORATION OF NEW JERSEY risers-non nnnennr Ho Drawing.

This invention relates to reagents for use in the separation of valuable minerals from their ores by flotation and to the process of preparing and using thisreagent for flota: tion purposes. It relates more partlcularly to reagents of this character that are prepared from certain tar distillates or extractions therefrom.

This application is in part a continuation of our application Serial No. 751,696, filed November 22, 1924.

Those crude tars which are commercially known as coal tar, blast furnace tar, lignite tar, wood tar and others, contain acids whichv are commercially known as phenol, cresols and xylenols. These acids occur in those fractions of the tar distillate which are known as carbolic oil and creosote oil (both of which are sometimes designated as carbolic oil or middle oil). These acids are quite often separated, from any coal tar distillate in which they occur, by causin them to unite with caustic soda. Those acids to which we refer would, in most cases, be those which are extractable from the above tars or distillates by caustic soda.

By the present invention a very uniform, stable and satisfactory reagent for flotation purposes is produced. In carrying out this invention sulphur is caused to unite with tar acids (phenol, cresols or xylenols) and the resulting reagent may be used in its concentrated form ,for flotation purposes or may be mixed with coal tar, coal tar oil or other oil and thus used as a flotation agent. I

As a specific illustration of practicing this invention, but by which we do not intend to be limited, it may be stated that a very efficient and simple method is to add disulfurdichloride to either crude or purified tar acids such as phenol, cresols or xylenols. The observed results seem to indicate that sulphur from the disulfur-dichloride replaces hydrogen from the acid and hydrochloric gas is generated and evolved. Some form of phenyl, cresyl and xylenyl sulphides or other sulphur compounds seem to be formed and remain indefinitely combined without serious decomposition of the same or deposition of disulfur-dichloride.

Application fled January 29, 1925. Serial no. cam. v p

sulphur taking place even upon long stand- %)ur experiments have proven that, when tar acids are treated with disulphur-dichloride without moderating the heat of reaction, a substitution of sulphur in the benzene ring takes place, resulting in the formation of a dihydroxy-disulfide. In factwe have found that when phenol itself is sulfidized, such as by the treatment thereof with disulfur-dichloride and taking advantage of the heat oi reaction developed, dihydroxy-diphen l-disulfide is produced. This compoun has been discovered by us to be an excellent flotar it has been found that about 10 to 50% by volume-of the total reacting mass shouldj be disuIfur-dichloride or, in other words, 100 parts by volume of tar acids should be treated with about 10 to 100 parts by volume of The reagent thus producedmay be used as such for flotation purposes by adding the reagent directly to the agltated mineral pulp, or in solution in a dispersing a t, such as tars or oils of various types. Th n: shipping and handling costs are reduced to a because it maybe necessary to supply. the reagent from a remote point, whereas the dispersing agent, such as tars or oils as ma be dichloride to coal tar oils such as acid bearmg creosote or light creosote oil, for example, containing tar acids such as phenols or cresols and the mixture used for mineral flotation. The observed results seem to indicate that sulfur from the disulfur-dichloride replaces hydrogen from the oil or acid and hydrochloric acid gas .is generated and' usually require about 1% to 25% of disulfur-dichloride by volume. 25% is about the upper limit for oils containing as high as v 25% of tar acids. By testing samples of any particular oil the best proportions for that oil can be ascertained. Some high acid tars are themselves susceptible to this treatment and the treated acids may be combined with tars as well as distillates. In practicing the invention it has'been found that widely different grades of oil or tar can be treated so as to obtain a satisfactory product, and that this modification of the invention is not restricted to high grade refined oil.

From the above description, it will readily be seen that the practice of this invention is notconfined to highly refined tar acids or to tar acids of any particular class, exce t that they should be monohyd-ric phenols. mpure tar acids or mixtures thereof may similarly be treated. It has been found that there is some little difl'erence in results when sulfidized phenol, cresols or xylenols are used or when a mixture of tar acids which have been sulfidized are used. However, this does not vary the broad principle of applicants invention which is the discovery of a valuable flotation reagent or series of reagents, regardless of the method of their production.

Some of the advantages of our invention are that the product can be made more uniform than was possible by processes heretofore known; the product is much more stable than those heretofore known and the results obtained by using this product for flotation purposes are better and more uniform than are possible with prior known products.

In describing and claiming this invention the various terms used are intended as follows: Coal tar includes those tars that are commercially known as coal tar, water gas such tars as commercial coal tar, blast an 'disulfur-dichloride by volume to 100 parts of tar acid.

2. The process which comprises treating coal tar oil containing tar acid with disulfurdichloride, using about 15 parts of disulfurdichloride by volume to 100 parts of tar acid.

3. The process which comprises treating coal tar containing tar acid with disulfurdichloride, using about 1.5 parts of disulfurdicliiloride by volume to 100 parts of tar ac1 4. The process which comprises treating coal tar containing tar acid with disulfurdichloride, using about 10 to 40 parts of disulfur-dichloride by volume to 100 parts of tar acid.

5. A composition of matter comprising the reaction product obtainable by reacting, while hot," a coal tar acid and disulfur-dichloride.

6. A composition of matter comprising the reaction product of disulfur-dichloride with a mixture of phenols obtainable by the extraction of a coal tar distillate with sodium hydroxide solution.

7. A composition of matter comprising the reaction product obtainable by reacting, while hot, phenol and disulfur-dichloride.

8. A composition of matter comprising the reaction product obtainable by reacting, while hot, a cresol and disulfur-dichloride.

9. A composition of matter comprising the reaction product obtainable by reacting, while hot, a xylenol and disulfur-dichloride.

10. The process which com rises treating a coal tar acid with disnlfurichloride.

11. The process which comprises reacting a hot mixture of a coal tar acid and disulfurdichloride.

12. The process which com rises reacting disulfur-dichloride with a mixture of phenols obtainable by the extraction of a coal tar distillate with sodium hydroxide solution.

13. The process which comprises reacting a hot mixture of disulfur-dichloride with a mixture of phenols obtainable by the extraction of a coal tar distillate with sodium hydroxide solution.

14:. A composition of matter comprising 'coal tar and a compound obtainable by the reaction of a coal tar acid and disulfur-dichloride.

15. A composition of matter comprising coal tar and the reaction product of dlsulfur dichloride with a mixture of phenols chtainable by the extraction of coal tar distillato with sodium hydroxide solution. I

v 16. A composition of matter comprising dihydroxy-diphenyl-disulfide and coal tar.

17. A composition of matter comprising dilhydroxy-diphenyl-disulfide and coal tar 01 In testimony whereof we afiix our signatures.

FREDERICK G. MOSES.

EDWARD J. CANAVAN. 

